“To subsidize” in Chinese is 资助 (zīzhù).
她拒绝了我的资助。
She turned down the subsidy that I offered.
Example sentence from Tatoeba (CC BY 2.0).
Not to be confused with: 自助 (zìzhù, self-service) · 自主 (zìzhǔ, to act independently; to be autonomous; to be in control of one's own affairs)